Linkage mechanism

ABSTRACT

A linkage mechanism for coupling walls of a container such as for interconnecting the sections of a hogshead or like container. There is provided link members connected to adjacent wall sections of a hogshead or like container, which link members interconnect and cooperate to draw the wall sections together and to hold them in assembled position, and which permit separation of the wall sections as desired. This is an abstract only of the specific illustration of the invention given by way of example, and is not to be used in the interpretation of the claims nor as a limitation on the scope of the invention.

[ LINKAGE MECHANISM [75] Inventor: William 0. Setele, Independence,

Ohio

[73] Assignee: Kendale Industries, Inc.,

Independence, Ohio 22 Filed: Sept. 30, 1971 211 App]. No.: 185,207

2,514,829 7/1950 Barkley, .lr .1 217/44 2,884,176 4/1959 Carpenter et a1 292/256.69 UX 2,966,378 12/1960 Carpenter et al 292/256.69

Primary Examiner-Herbert F. Ross Assistant Examiner-James R. Garrett Att0rneyWoodling, Krost et al.

[57] ABSTRACT A linkage mechanism for coupling walls of a container such as for interconnecting the sections of a hogshead or like container. There is provided link members connected to adjacent wall sections of a hogshead or like container, which link members interconnect and cooperate to draw the wall sections together and to hold them in assembled position, and which permit separation of the wall sections as desired. This is an abstract only of the specific illustration of the invention given by way of example, and is not to be used in the interpretation of the claims nor as a limitation on the scope of the invention.

11 Claims, 4 Drawing Figures PATENTEUuuv 6197s 3770.157

L INVENTOR. Fig. 4 W/LL/AM 0.557115 W /1," I 7/ 1 M w ATTOPNEYfi LINKAGE MECHANISM An object of my invention is to provide improved means for coupling together wall sections of a container and to permit ready separation of the wall sections as desired.

Another object is the provision for ready assembling and dis-assembling of sections of a container such as a hogshead.

Another object is the provision of means readily adapted for assembling and dis-assembling sections which may be flat in the knocked-down condition and which may be in cylindrical form when in assembled condition.

Another object is the provision for obtaining leverage in the assembling and dis-assembling of walls of a container through an appropriate linkage mechanism of the herein described structure.

Other objects and a fuller understanding of this invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a plan view of a knocked-down half-section of a hogshead embodying the linkage mechanism of my invention, it being understood that another similar section may be utilized for forming the other half-cylinder of the hogshead;

FIG. 2 is a view of a wrench utilizable in the swinging of the link members of my improved linkage mechanism;

FIG. 3 is a planned view of my improved linkage mechanism in assembled condition and shown as mounted upon a portion of a hogshead; and

FIG. 4 is a cross-sectional view through the assembled linkage mechanism taken along the line 4-4 of FIG. 3.

It is to be understood that the view of FIG. 1 is on a greatly reduced scale in order to show the half-section of the hogshead to which the several link members shown in FIGS. 3 and 4 are mounted. The link mem-' bers shown in FIG. 1 are much reduced from the size of the link members shown in the linkage mechanism illustrated in FIGS. 3 and 4.

The half-section of a hogshead or similar container is indicated generally by the reference character 11. The preferred embodiment would be two of these sections 11 although there could be more than two in making up a complete hogshead. It is to be understood of course that end closures would be mounted or secured to the cylinder made up of two sections 11. If desired, a complete hogshead could be made of one long section 11 having a length sufficient to form the complete circumferential extent of the hogshead.

The section 11 of the hogshead is made up of a plurality of vertically disposed wooden slats or staves l2 bound together by a plurality of horizontally disposed metal bands 13 riveted or otherwise secured to the staves. Connected to the opposite ends of each end section of the section 11, and particularly to the end sections of the bands 13, are complementary link members adapted to be coupled together for interconnecting adjacent edge portions of the hogshead when sections are curved and joined with like sections to form a complete cylinder, as seen in FIG. 1 the link members at the opposite ends of the section 11 are of different structures are so arranged as to complementally interfit with an unlike link member on an adjoining wall section which is in abutment therewith.

The detailed structure of the coupling mechanism is best shown in connection with FIGS. 3 and 4 as showing the complementary link members coupled together so as to draw together and connect adjoining edge sections of the walls of the hogshead.

One of the link members, referred to as a first link member, is denoted by the reference character 14. The first link member 14 has offset portion 14A intermediate of its ends as shown in the drawing. One end of the first link member 14 is pivotally connected by means of the first pivot connection 15 to a first wall portion made up of a stave l2 and band 13, the pivot connection 15 extending through both the band and the stave. By means of the pivot connection 15, the first link member 14 may be pivotally swung in a plane substantially at right angles to the axis of the pivot connection 15 and generally parallel to the plane of the adjacent wall section.

The first link member 14 has a hole 16 extending therethrough near its free end remote from the pivot connection 15. This hole 16 has a wide portion 16A and a narrow portion 168, the narrow portion 168 being closest to the free end of the link member 14. The two portions 16A and 16B communicate with each other whereby there is direct passage between the two portions.

To differentiate between the two abutting wall sections the wooden staves in FIGS. 3 and 4 on the right side have been indicated by the reference character 12A, whereas those on the left side have been indicated by the reference character 12. Similarly, the right-hand side of the band at the abutting walls has been indicated by the reference character 13A to distinguish it from the other end of the band. A second link member 18 is pivotally connected to the second wall portion of the two abutting wall portions by means of the second pivot connection 19 extending through a stave 12A and band 13A. By means of the pivot connection 19 the second link member 18 may be pivotally swung in a plane at right angles to the axis of the pivot connection 19 and generally parallel to the plane of the adjacent wall section.

The second link member 18 has a knob or stud 20 formed by upsetting a portion of the metal of the second link member to provide the structure indicated. This knob or stud 20 has a head or enlarged portion 20A and a neck or reduced portion 208 disposed between the head 20A and the main portion of the second link member 18.

There is enough play or sloppiness in the parts to permit the head 20A to be axially thrust through the wide portion 16A of the hole 16 in the first link member 14. However, the head 20A of the knob 20 is too large to axially pass through the narrow portion 16B of hole 16. Nevertheless, the neck or reduced portion 208 can readily pass through the narrow portion 168 when slid from the wide portion 16A laterally into the narrow portion 168. Extending through the knob or stud 20 is an opening 21. Also extending through the second link member 18 near the free end thereof is another opening 22. These openings 21 and 22 are adapted to complementally receive spaced studs 28 nd 29 extending outwardly from a wrench 27. By an operator seizing the wrench 27 and inserting the studs 28 and 29 into the openings 21 and 22, respectively, leverage may be applied for manually swinging the second link member 18 about the pivot axis of the pivot connection 19. The

wrench 27 may, however, by readily removed by withdrawing the studs 28 and 29 from the openings 21 and 22.

Secured to a wall section made up of stave 12A and band 13A at that end of the hogshead section is a pin 23 protruding outwardly into the path of the second link member as it is swung in a plane parallel to the adjacent wall section. This pin 23 has a teflon, celcon or nylon collar secured under its head so as to provide a resiliently yieldable neck at that location. The pin 23 carrying the resiliently yieldable collar 24 is positioned so as to enter a notch formed in a side edge of the second link member near its free end as shown in the drawing. This notch 25 has a relatively narrow throat or entrance and a slightly larger inner portion or recess. Upon swinging of the second link member 18 firmly against the pin 23, the pin 23 enters the notch 25 against the resiliently yieldable resistance of the collar 24. However, because of the slightly larger dimension of the inner portion or recess of the notch 25, the collar 24 may expand at that location. Therefore the resiliently yieldable collar is such to resiliently resist both ingress into the notch 25 and egress from the notch 25. This arrangement provides for a locking of the second link member 18 into the position shown in FIGS. 3 and 4 at the same time it permits the second link member to be pivotally swung away from the pin 23 and thus to unlock the second link member from its locked position.

For assembling a hogshead two sections like section 11 are curved or bent into semi-cylindrical shapes. This brings unlike link members into juxtaposition. The stud 20 carried by a second link member is inserted into a hole 16 of a first link member connected to the next adjacent wall section at the joinder of two wall sections. When in this position, the two link members are swung askew from the positions shown in FIGS. 3 and 4 and are disposed at an angle to each other. With the knob 20 in a hole 16 at the location of its wide portion 16A the second link member 18 is swung on its pivot con nection in a direction away from the pivot connection of the first link member 14. In the disposition of the parts shown in FIG. 3, this would be a swinging of the second link member 18 downwardly. This causes the knob 20 to move into the narrow portion 168 of hole 16 and the second link member upon moving downwardiy toward the position shown in FIG. 3 causes the first link member to also pivotally swing on its pivot connection 15 downwardly to the position shown in FIG. 3. When in this position the pin 23 enters the notch 25 and is locked therein by the collar 24. The two links members 14 and 18 are then in the overlapped and generally parallel relationship illustrated in FIGS. 3 and 4. The two adjoining wall sections of the hogshead are drawn together to be closely adjacent thereto as illustrated. This closes or couples together the adjoining wall sections of the hogshead. For the purpose of obtaining sufficient force to draw the wall sections together, the wrench 27 may be applied to the second link member 18 to forcibly swing it into position and to cause the collar 24 to enter the notch 25.

When it is desired to uncouple or open up the adjoining wall sections, a second link member is swung upwardly or in a reverse direction and this causes the first link member to also swing upwardly and this causes separation or wider spacing between the two adjoining sections of the hogshead. When in this position the knob 20 may be moved axially out of the opening 16 by the permitted play between the parts. The hogshead may thus be disassembled by uncoupling all of the complementary link members along the adjoining edges.

In the use of a hogshead for the shipping of tobacco, it is sometimes desired to open up or separate the wall sections without actually disassembling the sections. For this purpose the second link member may be swung upwardly in FIG. 3 and this will also swing upwardly the first link member 14 to where the link members are dis posed at an angle to each other. When in this position, access may be had to the interior of the hogshead through the crack or opening provided between the sections,.for the withdrawing of samples of the tobacco such as in the inspection process. After the inspection process is completed by the withdrawing of a sample, the link members may be readily moved back to the as sembled position shown in FIGS. 3 and 4, advantageously with he use of a wrench 27, and this will again close or couple the adjoining sections of the hogshead.

After the use of the hogshead for the shipping of tobacco or the like has been completed, the hogshead may be readily disassembled and shipped back in a flattened condition. An example of the flattened condition of a hogshead section is shown in FIG. 1, thus less shipping volume is required in the sending of the empty hogshead disassembled into flat sectional form. Of course, the end closures are also removed from the cylinder made up of the hogshead sections when being shipped in disassembled condition.

While this disclosure is directed particularly to the use of my improved linkage mechanism for joining hogshead sections, it is to be understood that the same linkage mechanism may be adapted and used for joining other wall sections such as adjacent wall sections of other containers and the like.

The present disclosure includes that contained in the appended claims, as well as that of the foregoing description.

Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

1. Linkage mechanism for connecting a first wall and a second wall of a container, said walls having opposed edge portions adapted to be brought into close proximity upon connection of said walls, said mechanism comprising in combination a first link member pivotally connected to said first wall adjacent the edge portion thereof and swingable in a plane generally parallel to the plane of said first wall to extend toward the edge portion of said second wall, said first link member having a hole therethrough adjacent the free end thereof, said hole having a first portion and a second portion nearer the free end of the link than the first portion merging with the first portion, a second portion being narrower than said first portion, a second link member pivotally connected to said second wall adjacent the edge portion thereof swingable in a plane generally parallel to the plane of said second wall to extend toward the edge portion of said first wall, said second link member having a knob extending from the face thereof remote from said second wall and at a distance from its pivotal connection with said second wall, said knob having a head portion and a neck portion interposed between the head portion and second link member, said neck portion being of less transverse dimension than said head portion, said head portion being of a cross-sectional size as to pass readily through the first portion of said hole in said first link member but not through said second portion of the said hole upon relative axial movement of the knob and said hole, said second link member having a locking notch provided in a side edge thereof adjacent the free end of the second link member, said notch having an inner portion and a throat portion extending to said inner portion, said throat portion being narrower than said inner portion, and a locking pin secured to said first wall and extending outwardly therefrom into the path of said second link member upon the pivotal swinging of the said second link member toward said locking pin, said locking pin having a resiliently yieldable portion adapted to be pressed through the throat portion of said notch in tight interfit therewith into the said inner portion to be locked therein by the resiliently yieldable resistance of said neck portion outwardly through said throat portion, the combination of said first link member, said second link member, and said locking pin being such that upon said knob being positioned in said hole and the said second link member being pivotally swung away from said first wall the neck portion of the knob moves into the second portion of the said hole and the first link member is swung by the second link member to position the first and second link members in parallel overlying juxtaposition whereby the said walls are drawn together and the opposed edge portions thereof placed in close proximity with each other, the pivotal swinging of the second link member toward said locking pin to position the locking pin in the inner portion of said notch resiliently locking the second link member in said parallel juxtaposition with said first link member.

2. Linkage mechanism as claimed in claim 1, and including spaced engaging means carried by the second link member for engagement by a lever having complementary spaced engaging means and extending longitudinally of, and from, the second link member to provide leverage in pivotally swinging of said second link member.

3. Linkage mechanism as claimed in claim 2 and including in the combination the said lever.

4. Linkage mechanism as claimed in claim 2 and in which a first of said spaced engaging means is provided by an opening through said knob and a second of said spaced engaging means is provided by an opening through said second link member adjacent the free end thereof.

5. Linkage mechanism for coupling adjacent first and second separable wall portions of a container in edge abutting relationship comprising in combination a first link member pivotally connected to the first wall portion to be pivotally swung in a plane adjacent and generally parallel to the said first wall portion, second link member pivotally connected to the said second wall portion to be pivotally swung in a plane adjacent and generally parallel to said second wall portion, complementary connecting means carried by said first and second link members and disposed for selective interengagement to pivotally connect said link members at a location spaced from their respective pivot connections with the, said wall portions, said complementary connecting means when interengaged and upon swinging said first link member and in a plane generally parallel to the plane of the second link member, toward a closing position in which the first link member overlaps said second link member and extends in the same direction away from the pivot connection of said first link member with the first wall portion and upon the second link member being pivotally swung away from the said pivot connection of said first link member, the said swinging of the first link member to said closing position drawing toward each other and coupling the first and second wall portions pivotally connected to said first and second link members, respectively, resiliently yieldable interengageable locking means carried by the second link member and second wall portion for selectively holding said second link member in said closed position for maintaining said wall portions coupled, said resiliently yieldable interengageable locking means including a notch in a side edge of the second link member and a pin carried by said second wall portion in a position to enter said notch upon the second link member being swung to said closed position, said pin and notch having close fitting opposed surfaces at least one of which is resiliently yieldable to provide resiliently yieldable resistance to the entry of the pin into the notch and to egress therefrom.

6. Linkage mechanism for coupling adjacent first and second separable wall portions of a container in edge abutting relationship comprising in combination a first link member pivoally connected to the first wall portion to be pivotally swung in a plane adjacent and generally parallel to the said first wall portion, a second link member pivotally connected to the said second wall portion to be pivotally swung in a plane adjacent and generally parallel to said second wall portion, complementary connecting means carried by said first and second link members and disposed for selective interengagement to pivotally connect said link members at a location spaced from their respective pivot connections with the said wall portions, said complementary connecting means when interengaged and upon swinging said first link member and in a plane generally parallel to the plane of the second link member, toward a closing position in which the first link member overlaps said second link member and extends in the same direction away from the pivot connection of said first link member with the first wall portion and upon the second link member being pivotally swung away from the said pivot connection of said first link member, the said swinging of the first link member to said closing position drawing toward each other and coupling the first and second wall portions pivotally connected to said first and second link members, respectively, said complementary pivot connections carried by the first and second link members comprising a knob extending outwardly from the second link member and a hole in the first link member for accommodating the said knob therein, said knob having a head and a neck and said hole having a first portion sufficiently large to accommodate the movement of the head of the knob therethrough for interengagement of the knob and hole, said hole having a second portion communicating with said first portion sufficiently large to accommodate the neck of the knob therein but sufficiently small to prevent movement of the head of the knob therethrough, said second portion of the hole being disposed to receive the neck of the knob therein upon the swinging of the second link member toward said closed position.

7. Linkage mechanism as claimed in claim 6 and in which said knob has a first opening therethrough and said second link member has a second opening therein spaced from said first opening, said first and second openings being arranged to accommodate the lugs of a lever for the swinging by leverage of said second link member.

8. Linkage mechanism or drawing together toward a closed position, and coupling in the closed position, two separable wall portions disposed in generally the same plane comprising in combination a first link member, a first pivot connection connecting the first link member to a first wall portion to swing in a plane generally parallel to said first wall portion, a second link member, a second pivot connection connecting the second link member to a second wall portion to swing in a plane generally parallel to said second wall portion, a third pivot connection connecting said first and second link members at a distance along the first link member from the first pivot connection and at a distance along the second link member from the second pivot connection, the swinging of the second link member on said second pivot connection in a direction away from said first pivot connection moving the first link member through said third pivot connection to swing on said first pivot connection in a corresponding direction to cause the first and second link members to be disposed in parallel overlapping relationship in general alignment with the first and second pivot connections, the moving of said link members to such parallel overlapping relationship drawing toward each other the said first and second wall portions to which the said first and second link members, respectively, are pivotally connected, said third pivot connection comprising a stud carried by one of the link members and a hole in the other link member accommodating said stud, said stud and hole being formed to permit the stud to move axially through the hole in one position of the link members relative to each other and to lock the stud in the hole in another position of the link members relative to each other.

9. Linkage mechanism as claimed in claim 8, and including spaced engaging means carried by said second link member and adapted to engage spaced portions of a lever extending along and outwardly from the second link member for pivotally swinging with leverage the second link member.

10. Linkage mechanism as claimed in claim 9 and in which said spaced engaging means are provided by an opening extending through said stud and by an open space in the second link member adjacent the free end thereof.

11. Linkage mechanism for drawing together toward a closed position, and coupling 1 the closed position, two separable wall portions disposed in generally the same plane comprising in combination a first link member, a first pivot connection connecting the first link member to a first wall portion to swing in a plane generally parallel to said first wall portion, a second link member, a second pivot connection connecting the second link member to a second wall portion to swing in a plane generally parallel to said second wall portion, a third pivot connection connecting said first and second link members at a distance along the first link member from the first pivot connection and at a distance along the second link member from the second pivot connection, the swinging of the second link member on said second pivot connection in a direction away from said first pivot connection moving the first link member through said third pivot connection to swing on said first pivot connection in a corresponding direction to cause the first and second link members to be disposed in parallel overlapping relationship in general alignment with the first and second pivot connections, the moving of said link members to such parallel overlapping relationship drawing toward each other the first and second wall portions to which the said first and second link members, respective, are pivotally connected, and including resilient locking means interengageable with said second link member for selectively holding the second link member in said parallel overlapping relationship in general alignment with said first and second pivot connections, said resilient locking means comprising a notch in the side edge of the second link member and a pin carried by the second wall portion in the swinging path of the second link member to enter said notch upon the second link member being swung to said parallel overlapping relationship in general alignment with said first and second pivot connections, said pin and notch having close fitting interengageable surfaces one of which is resiliently yieldable to provide resiliently yieldable resistance to ingress of the pin into the notch and to egress of the pin from the notch, 

1. Linkage mechanism for connecting a first wall and a second wall of a container, said walls having opposed edge portions adapted to be brought into close proximity upon connection of said walls, said mechanism comprising in combination a first link member pivotally connected to said first wall adjacent the edge portion thereof and swingable in a plane generally parallel to the plane of said first wall to extend toward the edge portion of said second wall, said first link member having a hole therethrough adjacent the free end thereof, said hole having a first portion and a second portion nearer the free end of the link than the first portion merging with the first portion, a second portion being narrower than said first portion, a second link member pivotally connected to said second wall adjacent the edge portion thereof swingable in a plane generally parallel to the plane of said second wall to extend toward the edge portion of said first wall, said second link member having a knob extending from the face thereof remote from said second wall and at a distance from its pivotal connection with said second wall, said knob having a head portion and a neck portion interposed between the head portion and second link member, said neck portion being of less transverse dimension than said head portion, said head portion being of a cross-sectional size as to pass readily through the first portion of said hole in said first link member but not through said second portion of the said hole upon relative axial movement of the knob and said hole, said second link member having a locking notch provided in a side edge thereof adjacent the free end of the second link member, said notch having an inner portion and a throat portion extending to said inner portion, said throat portion being narrower than said inner portion, and a locking pin secured to said first wall and extending outwardly therefrom into the path of said second link member upon the pivotal swinging of the said second link member toward said locking pin, said locking pin having a resiliently yieldable portion adapted to be pressed through the throat portion Of said notch in tight interfit therewith into the said inner portion to be locked therein by the resiliently yieldable resistance of said neck portion outwardly through said throat portion, the combination of said first link member, said second link member, and said locking pin being such that upon said knob being positioned in said hole and the said second link member being pivotally swung away from said first wall the neck portion of the knob moves into the second portion of the said hole and the first link member is swung by the second link member to position the first and second link members in parallel overlying juxtaposition whereby the said walls are drawn together and the opposed edge portions thereof placed in close proximity with each other, the pivotal swinging of the second link member toward said locking pin to position the locking pin in the inner portion of said notch resiliently locking the second link member in said parallel juxtaposition with said first link member.
 2. Linkage mechanism as claimed in claim 1, and including spaced engaging means carried by the second link member for engagement by a lever having complementary spaced engaging means and extending longitudinally of, and from, the second link member to provide leverage in pivotally swinging of said second link member.
 3. Linkage mechanism as claimed in claim 2 and including in the combination the said lever.
 4. Linkage mechanism as claimed in claim 2 and in which a first of said spaced engaging means is provided by an opening through said knob and a second of said spaced engaging means is provided by an opening through said second link member adjacent the free end thereof.
 5. Linkage mechanism for coupling adjacent first and second separable wall portions of a container in edge abutting relationship comprising in combination a first link member pivotally connected to the first wall portion to be pivotally swung in a plane adjacent and generally parallel to the said first wall portion, second link member pivotally connected to the said second wall portion to be pivotally swung in a plane adjacent and generally parallel to said second wall portion, complementary connecting means carried by said first and second link members and disposed for selective interengagement to pivotally connect said link members at a location spaced from their respective pivot connections with the said wall portions, said complementary connecting means when interengaged and upon swinging said first link member and in a plane generally parallel to the plane of the second link member, toward a closing position in which the first link member overlaps said second link member and extends in the same direction away from the pivot connection of said first link member with the first wall portion and upon the second link member being pivotally swung away from the said pivot connection of said first link member, the said swinging of the first link member to said closing position drawing toward each other and coupling the first and second wall portions pivotally connected to said first and second link members, respectively, resiliently yieldable interengageable locking means carried by the second link member and second wall portion for selectively holding said second link member in said closed position for maintaining said wall portions coupled, said resiliently yieldable interengageable locking means including a notch in a side edge of the second link member and a pin carried by said second wall portion in a position to enter said notch upon the second link member being swung to said closed position, said pin and notch having close fitting opposed surfaces at least one of which is resiliently yieldable to provide resiliently yieldable resistance to the entry of the pin into the notch and to egress therefrom.
 6. Linkage mechanism for coupling adjacent first and second separable wall portions of a container in edge abutting relationship comprising in combination a first link member pivoally connected to the first wall Portion to be pivotally swung in a plane adjacent and generally parallel to the said first wall portion, a second link member pivotally connected to the said second wall portion to be pivotally swung in a plane adjacent and generally parallel to said second wall portion, complementary connecting means carried by said first and second link members and disposed for selective interengagement to pivotally connect said link members at a location spaced from their respective pivot connections with the said wall portions, said complementary connecting means when interengaged and upon swinging said first link member and in a plane generally parallel to the plane of the second link member, toward a closing position in which the first link member overlaps said second link member and extends in the same direction away from the pivot connection of said first link member with the first wall portion and upon the second link member being pivotally swung away from the said pivot connection of said first link member, the said swinging of the first link member to said closing position drawing toward each other and coupling the first and second wall portions pivotally connected to said first and second link members, respectively, said complementary pivot connections carried by the first and second link members comprising a knob extending outwardly from the second link member and a hole in the first link member for accommodating the said knob therein, said knob having a head and a neck and said hole having a first portion sufficiently large to accommodate the movement of the head of the knob therethrough for interengagement of the knob and hole, said hole having a second portion communicating with said first portion sufficiently large to accommodate the neck of the knob therein but sufficiently small to prevent movement of the head of the knob therethrough, said second portion of the hole being disposed to receive the neck of the knob therein upon the swinging of the second link member toward said closed position.
 7. Linkage mechanism as claimed in claim 6 and in which said knob has a first opening therethrough and said second link member has a second opening therein spaced from said first opening, said first and second openings being arranged to accommodate the lugs of a lever for the swinging by leverage of said second link member.
 8. Linkage mechanism or drawing together toward a closed position, and coupling in the closed position, two separable wall portions disposed in generally the same plane comprising in combination a first link member, a first pivot connection connecting the first link member to a first wall portion to swing in a plane generally parallel to said first wall portion, a second link member, a second pivot connection connecting the second link member to a second wall portion to swing in a plane generally parallel to said second wall portion, a third pivot connection connecting said first and second link members at a distance along the first link member from the first pivot connection and at a distance along the second link member from the second pivot connection, the swinging of the second link member on said second pivot connection in a direction away from said first pivot connection moving the first link member through said third pivot connection to swing on said first pivot connection in a corresponding direction to cause the first and second link members to be disposed in parallel overlapping relationship in general alignment with the first and second pivot connections, the moving of said link members to such parallel overlapping relationship drawing toward each other the said first and second wall portions to which the said first and second link members, respectively, are pivotally connected, said third pivot connection comprising a stud carried by one of the link members and a hole in the other link member accommodating said stud, said stud and hole being formed to permit the stud to move axially through the hole in one position of the link members relative to Each other and to lock the stud in the hole in another position of the link members relative to each other.
 9. Linkage mechanism as claimed in claim 8, and including spaced engaging means carried by said second link member and adapted to engage spaced portions of a lever extending along and outwardly from the second link member for pivotally swinging with leverage the second link member.
 10. Linkage mechanism as claimed in claim 9 and in which said spaced engaging means are provided by an opening extending through said stud and by an open space in the second link member adjacent the free end thereof.
 11. Linkage mechanism for drawing together toward a closed position, and coupling 1 the closed position, two separable wall portions disposed in generally the same plane comprising in combination a first link member, a first pivot connection connecting the first link member to a first wall portion to swing in a plane generally parallel to said first wall portion, a second link member, a second pivot connection connecting the second link member to a second wall portion to swing in a plane generally parallel to said second wall portion, a third pivot connection connecting said first and second link members at a distance along the first link member from the first pivot connection and at a distance along the second link member from the second pivot connection, the swinging of the second link member on said second pivot connection in a direction away from said first pivot connection moving the first link member through said third pivot connection to swing on said first pivot connection in a corresponding direction to cause the first and second link members to be disposed in parallel overlapping relationship in general alignment with the first and second pivot connections, the moving of said link members to such parallel overlapping relationship drawing toward each other the first and second wall portions to which the said first and second link members, respective, are pivotally connected, and including resilient locking means interengageable with said second link member for selectively holding the second link member in said parallel overlapping relationship in general alignment with said first and second pivot connections, said resilient locking means comprising a notch in the side edge of the second link member and a pin carried by the second wall portion in the swinging path of the second link member to enter said notch upon the second link member being swung to said parallel overlapping relationship in general alignment with said first and second pivot connections, said pin and notch having close fitting interengageable surfaces one of which is resiliently yieldable to provide resiliently yieldable resistance to ingress of the pin into the notch and to egress of the pin from the notch. 